Folding chair

ABSTRACT

A folding chair comprising a seat and a backrest carried by a folding structure, wherein the folding structure comprises a first structure defining a pair of front legs and a second structure defining a pair of rear legs, articulated to each other about a transverse axis by means of a pair of joints and movable relative to one another between an open position and a closed position, wherein the first structure comprises two first side elements and the second structure comprises two second side elements and wherein each of said joints comprises a first half-joint fixed to a respective first side element and a second half-joint fixed to a respective second side element, wherein the first and the second half-joints are rotatable relative to one another about said transverse axis, wherein the first structure comprises a pair of rods mounted within respective first side elements and movable between a raised position and a lowered position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit of Italian patent application number102015000015872, filed May 19, 2015, which is herein incorporated byreference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a folding chair comprising a foldingsupport structure movable between an open position and a closed positionand carrying a seat and a backrest.

Description of Prior Art

The U.S. Pat. No. 3,705,744 by the same inventor describes a foldingchair in which the backrest is fixed to a rectangular frame defining thefront legs and in which a second U-shaped frame defining the rear legsis articulated to the first frame about a transverse axis. The seat isarticulated around the same transverse axis.

The U.S. Pat. No. 5,524,966 by the same owner describes a folding chairprovided with three structures defining, respectively, the front legs,the rear legs and the seat, which are mutually articulated about acommon transverse axis. The backrest of the chair forms part of a fourthstructure separate from said three structures and articulated on one ofthem about the common axis. In the conditions of use of the chair, thebackrest can tilt backwards against the action of a spring.

Folding chairs of this type have the disadvantage that the backrest isaligned to the structure defining the front legs. In the position ofuse, the backrest forms an angle greater than 90° relative to the seat.This makes the chair more uncomfortable with respect to non-foldingchairs in which the backrest is essentially perpendicular to the seat.If, on the other hand, the backrest in a folding chair was essentiallyperpendicular to the seat in the position of use, in the closed positionthe chair would have large overall dimensions.

SUMMARY OF THE INVENTION

The present invention aims to provide a chair that, in the position ofuse, has the same comfort conditions of a rigid chair and that occupiesa minimal amount of space in the storage position.

According to the present invention, this object is achieved by a chairhaving the characteristics forming the subject of claim 1.

The claims form an integral part of the disclosure provided here inrelation to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described in detail with reference tothe attached drawings, given purely by way of non-limiting example,wherein:

FIG. 1 is a side view of a chair according to the present invention inthe open position.

FIG. 2 is a side view of the chair of FIG. 1 in the closed position.

FIG. 3 is a perspective view of the chair according to the inventionwith the seat and the backrest in an exploded position.

FIG. 4 is a partially exploded perspective view of the part indicated bythe arrow IV in FIG. 3.

FIGS. 5 and 6 are perspective views in cross-section along the line V-Vof FIG. 3 in two positions of the backrest.

FIG. 7 is an exploded perspective view of the part indicated by thearrow VII in FIG. 4.

FIG. 8 is a perspective view from a different angle of the elementindicated by the arrow VIII in FIG. 7.

FIGS. 9 and 10 are cross-sections according to the line IX-IX of FIG. 7in the open position and in the closed position, respectively.

DETAILED DESCRIPTION

With reference to FIGS. 1 to 3, numeral 10 indicates a folding chairaccording to the present invention. The chair 10 comprises a foldingstructure 12 carrying a backrest 14 and a seat 16. The chair 10 iscapable of assuming an open position illustrated in FIG. 1 and a closedposition illustrated in FIG. 2.

The folding structure 12 comprises a first structure 18 and a secondstructure 20 articulated to each other about a transverse axis A bymeans of a pair of joints 22. The first structure 18 essentially has aU-shaped frame and comprises two first side elements 24 parallel to eachother and joined at their lower ends by a first transverse element 26.The first side elements 24 have lower portions 24 a that define thefront legs of the chair and upper portions 24 b that form supports forthe backrest 14.

The second structure 20 essentially has the shape of a rectangular frameand comprises two second side elements 28 parallel to each other havingrespective upper ends joined together by a second transverse element 30and respective lower ends joined together by a third transverse element32. The second side elements 28 have lower portions 28 a that define therear legs of the chair and upper portions 28 b that define supports forthe seat 16. The first and second side elements 24, 28 and the crossmembers 26, 30, 32 are formed by tubular elements.

With reference to FIG. 4, respective rods 34 are inserted within theupper portions 24 b of the first side elements 24. The rods 34 aremovable within the upper portions 24 b between a raised position and alowered position. Each rod 34 has an engagement portion 36 at its lowerend, formed for example by a transverse groove. With reference to FIGS.4-6, each rod 34 has an upper end portion 38 with a reduced diameter.Each rod 34 comprises a bushing 40 slidably mounted on the respectiveupper end portion 38. A stop element 42 is fixed to the upper end of therespective upper end portion 38 of the rod 34. A helical compressionspring 44 is arranged coaxially to the upper end portion 38 of therespective rod 34 and has opposite ends resting, respectively, against ashoulder of the rod 34 and against a lower front end of the bushing 40.The spring 44 pushes the bushing 40 upwards, into abutment against ahead of the stop element 42. The bushing 40 can be pushed downwardsalong the upper end portion 38 of the rod 34 against the action of thespring 44.

With reference to FIG. 3, the backrest 14 comprises a backrest panel 46and two supports 48 inserted and fixed within respective seats 50 of thebackrest panel 46.

With reference to FIGS. 4 to 6, each support 48 has a front articulationportion 52 and a rear articulation portion 54. The front articulationportion 52 of each support 48 is articulated to a respective firsteyelet 56 fixed to the upper end of the respective first side element24. The second articulation portion 54 is articulated to a second eyelet58 fixed to or integrally formed with the bushing 40 of the respectiverod 34. The articulation portions 52, 54 are articulated to therespective eyelets 56, 58 by means of respective pins 60, 62. The firstpin 60 rotatably engages respective holes of the articulation portion 52and of the corresponding eyelet 56 without radial clearance. The secondpin 62 engages the respective eyelet 58 with a certain clearance in theradial direction as shown in FIGS. 5 and 6.

With reference to FIG. 3, the seat 16 has side edges 64 equipped withtransverse articulation holes 66 (only one of which is visible in FIG.3). The holes 66 are engaged in a rotatable manner by the secondtransverse element 30 of the second structure 20. The front end of theseat 16 is therefore articulated about a transverse axis with respect tothe second structure 20. The opposite side edges 64 of the seat 16engage respective shoes 68 that are carried, in an oscillating mannerabout a common transverse axis, by the respective upper portions 24 b ofthe first side elements 24 of the first structure 18. The shoes 68 arepreferably fixed to respective pins that rotatably engage respectivebushings fixed to the respective upper portions 24 b. The shoes 68support the rear part of the seat 16 and slidably engage thecorresponding side edges 64 of the seat 16.

With reference to FIG. 7, each joint 22 comprises a first half-joint 70fixed to a respective first side element 24 and a second half-joint 72fixed to a respective second side element 28. The two half-joints 70, 72are coupled together rotatably about the transverse axis A by arespective pin 74. With reference to FIGS. 7 and 8, the pin 74 has ashank which rotatably engages a hole 80 of the first half-joint 70 andone end that is inserted and fixed into a hole 82 of the secondhalf-joint 72.

Preferably, the two half-joints 70, 72 are provided with respectivethrough-holes 76, 78 in which the first side element 24 and the secondside element 28 are, respectively, inserted and fixed. The twohalf-joints 70, 72 are rotatable relative to each other about the axisA, which coincides with the longitudinal axis of the pin 74. The axes ofthe holes 76, 78 are transverse and eccentric with respect to the axisA. With reference to FIGS. 9 and 10, the longitudinal axes B and C ofthe first side element 24 and of the second side element 28 are spacedapart from the transverse axis A. In the open position of FIG. 9, thepoint D—defined by the intersection between the longitudinal axes B andC of the first and second side elements 24, 28—is spaced apart from thetransverse axis A.

The second half-joint 72 carries a disc 84 having a central hole 86,which is passed through by the end portion of the pin 74. The disc 84has an inner face facing the first half-joint 70 and an outer facefacing the second half-joint 72. The disc 84 is rotationally fixed withrespect to the second half-joint 72. The rotational mounting of the disc84 with respect to the second half-joint 72 is obtained by means of apin 88 projecting from the outer face of the disc 84, which engages aneccentric hole 90 (FIG. 8) of the second half-joint 72. The disc 84 hasan actuating pin 92 and a stop pin 94 parallel to and eccentric withrespect to the axis A and projecting from the inner face of the disc 84.The actuating pin 92 extends through a hole 96 formed on the side wallof the first side element 24 and engages the engagement portion 36formed at the lower end of the rod 34. The stop pin 94 engages anarcuate seat 81 formed in the first half-joint 70.

The operation of the chair 10 according to the present invention is asfollows. The chair 10 is capable of assuming an open positionillustrated in FIG. 1 and a closed position illustrated in FIG. 2. Toswitch from the open position to the closed position, and vice versa,the two structures 18, 20 are rotated relative to one another about thetransverse axis A. During the relative rotation of the structures 18,20, the half-joints 70, 72 of each joint 22 rotate relative to oneanother about the transverse axis A. As illustrated in FIGS. 9 and 10,the relative rotation of the two half-joints 70, 72 of each joint 22involves a rotation of the actuating pin 92 and the stop pin 94 aboutthe transverse axis A. In the open position illustrated in FIG. 9, thestop pin 94 is in abutment against a lower end of the arcuate seat 81.The abutment between the pin 94 and the lower end of the arcuate seat 81defines a stable open position of the two structures 18, 20. In thisposition, the actuating pin 92 is in a raised position. Since theactuating pin 92 is engaged in the engagement portion 36 of therespective rod 34, in the open position of the chair 10, the rods 34 arein a raised position. In the raised position, the rods 34 move thebackrest 14 into a forward tilted position, as illustrated in FIGS. 1and 5. In this position, the backrest 14 is tilted forwards with respectto the longitudinal axis B of the first side elements 24 by an angleindicated by a in FIG. 1. In this position, the backrest 14 isessentially perpendicular to the seat 16.

When the two structures 18, 20 are rotated into the closed position, thetwo half-joints 70, 72 of each joint 22 rotate relative to one anotherabout the transverse axis A and are carried into the positionillustrated in FIG. 10. In this position, the stop pin 94 is in abutmentagainst an upper end of the arcuate seat 81 and defines a stroke-endposition of the closed chair. In this position, the drive pin 92 is in alowered position. During the movement from the open position to theclosed position, the drive pin 92 moves the respective rod 34 downwards,within the respective first side element 24. In the closed position ofthe chair 10, the rods 34 are in the lowered position. In this position,the backrest 14 is aligned to the longitudinal axis C of the sideelements 24, as shown in FIG. 2.

During the movement of the chair from the open position to the closedposition, the seat 16 tilts about the second transverse element 30located at the upper ends of the second side elements 28 and it isbrought into a position parallel to the second side elements 28 as shownin FIG. 2. In the closed position, the first side elements 24 and thesecond side elements 28 are parallel to each other.

In the open position, the backrest 14 can be inclined backwards againstan elastic force by a backward thrust applied by the user's back. In therest position, the springs 44 push the respective bushings 40 upwardsand the backrest supports 48 are in the position illustrated in FIG. 5.When the user applies a backward thrust against the backrest 14, thebackrest 14 tilts backwards about a transverse pivot axis defined by thecommon axis of the pins 60. During the backward tilt of the backrest 14,the bushings 40 move downwards compressing the respective springs 44.The position of maximum backward inclination of the backrest is reachedwhen the supports 48 come into abutment against the upper surfaces ofthe respective stop elements 42, as shown in FIG. 6. When the backwardthrust applied by the user against the backrest 16 ceases, the springs44 cause the backrest 14 to swing forward into the rest positionillustrated in FIG. 5. The maximum forward inclination position of thebackrest 14 is defined by the position of abutment of the bushings 40against the respective stop elements 42.

The chair according to the present invention has a more comfortablesitting position compared to traditional folding chairs because in theopen position the backrest 14 is essentially perpendicular to the seat16. The greater sitting comfort in the open position does not increasethe overall dimensions of the chair in the closed position because,during closing of the chair, the backrest 14 tilts backwards and in theclosed position the backrest 14 is aligned with the side elements 24,28.

Of course, without prejudice to the principle of the invention, thedetails of construction and the embodiments can be widely varied withrespect to those described and illustrated, without thereby departingfrom the scope of the invention as defined by the claims that follow.

The invention claimed is:
 1. A folding chair comprising: a seat and abackrest carried by a folding structure, wherein the folding structurecomprises a first structure defining a pair of front legs and a secondstructure defining a pair of rear legs, articulated to each other abouta transverse axis by means of a pair of joints and movable relative toone another between an open position and a closed position, wherein thefirst structure comprises two first side elements and the secondstructure comprises two second side elements and wherein each of saidjoints comprises a first half-joint fixed to a respective first sideelement and a second half-joint fixed to a respective second sideelement, wherein the first and the second half-joints are rotatablerelative to one another about said transverse axis, wherein the firststructure comprises a pair of rods mounted within respective first sideelements and movable between a raised position and a lowered position,wherein said joints cooperate with respective rods for controlling themovement of the rods from the raised position to the lowered position,and vice versa, as a consequence of the relative movement of the firststructure and the second structure from the open position to the closedposition, and vice versa, and wherein the backrest comprises twosupports each of which is articulated to a respective first side elementand to a respective rod, so that the movement of said rods from theraised position to the lowered position, and vice versa, controls themovement of the backrest with respect to the first structure between aposition of use and a storage position, and vice versa.
 2. A chairaccording to claim 1, wherein the second half-joint of each of saidjoints carries an actuating pin eccentric with respect to saidtransverse axis, which engages an engagement portion formed at a lowerend of a respective rod.
 3. A chair according to claim 2, wherein thesecond half-joint of each of said joints carries a stop pin, whichengages an arcuate seat formed in the corresponding first half-joint. 4.A chair according to claim 3, wherein said actuating pin and said stoppin are carried by a disc fixed with respect to said second half-joint.5. A chair according to claim 1, wherein each of said supports of thebackrest comprises a front articulation element articulated about atransverse axis to an upper end of a respective first side element and arear articulation element articulated to an upper end of a respectiverod.
 6. A chair according to claim 5, wherein each of said rodscomprises a bushing movable in a longitudinal direction with respect toan upper end portion of the rod and articulated to a respective reararticulation element of a respective support, each of said bushingsbeing associated with an elastic element that elastically pushes thebushing towards a raised position.
 7. A chair according to claim 1,wherein the seat has a front portion articulated to an upper end of saidsecond structure and wherein a rear portion of the seat rests on a pairof shoes carried by respective first side elements and oscillating withrespect to said first side elements about a transverse axis.
 8. A chairaccording to claim 7, wherein said shoes slidably engage respective sideedges of the seat in a longitudinal direction.